Spacetime Supersymmetry in a nontrivial NS-NS Superstring Background

TL;DR

This paper investigates superstring behavior in a nontrivial NS-NS background, revealing how the B_{} field affects spacetime supersymmetry and modifies the super-Poincare algebra.

Contribution

It constructs gauge-covariant super-Poincare generators in a nontrivial background and introduces a magnetic extension of the supersymmetry algebra.

Findings

B_{} field breaks spacetime supersymmetry spontaneously.

Spacetime momenta do not commute with supercharges in this background.

Magnetic super-Poincare generators obey an extended supersymmetry algebra.

Abstract

In this paper we consider superstring propagation in a nontrivial NS-NS background. We deform the world sheet stress tensor and supercurrent with an infinitesimal B_{\mu\nu} field. We construct the gauge-covariant super-Poincare generators in this background and show that the B_{\mu\nu} field spontaneously breaks spacetime supersymmetry. We find that the gauge-covariant spacetime momenta cease to commute with each other and with the spacetime supercharges. We construct a set of "magnetic" super-Poincare generators that are conserved for constant field strength H_{\mu\nu\lambda}, and show that these generators obey a "magnetic" extension of the ordinary supersymmetry algebra.